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Message: <blockquote data-quote="audioholic" data-source="post: 7094496" data-attributes="member: 549629">Not really. As Ive said several times now, cap voltage will follow system voltage. The cap wont 'try' to pull voltage, it will merely accept the voltage its given. Once the alt is insufficient to provide all the necessary power, and the cap follows the drop in voltage, the cap wont recharge until the system voltage increases. A few people here keep coming back to the idea that the cap and amp will pull current at the same time. This is fundamentally incorrect. Once voltage drops to 12.8 volts (for example, batt voltage), the cap will remain at 12.8 volts and not draw (or try to draw) current until system voltage is raised. At this point, the draw a cap places on system voltage will simply be that of its internal resistance.This may sound like Im a proponent of using external caps, but that is not true. Capacity becomes an issue at this point. The cap will drain its stored power very quickly, again to follow the drop in system voltage, and then it merely becomes an added strain on the alt/system voltage (in the form of its ESR). This added drain is not in the form of drawing the power to recharge (as recharging in this example would be to raise its own voltage), but in the form of merely being an added resistance (ESR) to the system that would otherwise not be there.Lets make this a bit simpler. To 'recharge' the cap would be to raise its voltage back to 14.4. If the amplifier is drawing enough power to lower to lower system voltage to 12.8 (batt voltage), its physically impossible for the cap to recharge to 14.4 volts. It cannot exist at 14.4 volts while the rest of the circuit is still holding at 12.8 volts. So you could say both the amp and cap will try to draw power at the same time, but reality is the cap will not actually pull the power from the alt until the alt has caught up and is raising system voltage above that 12.8.</blockquote>

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